This may be the only comment in the thread that actually addresses TFA, but what the heck.

CU used only two measures to establish their ranking: length of stay and mortality. Those are rather blunt instruments to measure quality. In their defense, their source data, which is collected by CMS, is poor at measuring outcomes more accurately than that. Actually, just about every national organization is poor at measuring medical outcomes, because there is often a large subjective component to how patients and their doctors rate outcomes.

Also, the data was somehow adjusted to reflect differences in acuity, but the methodology was not clear. ("The rates are adjusted to account for the fact that some hospitals treat older or sicker patients, and exclude data on patients who were transferred from other hospitals. These are often difficult cases that, CU felt, should not be counted against the receiving hospital.") Given that CU poached their data from CMS, I would guess that the "older and sicker" adjustment was based on the Case Mix Index, which for years has been inflated by hospitals to get more sweet, sweet gubmint reimbursement. It is probably fair to exclude transfers, but how do they account for the sicker patients with more complex conditions who are not transferred during the course of acute care, but are discharged from the referring hospital and are wheeled in to see a consultant at the specialty center and subsequently get their surgery done there?